In general, construction machinery such as wheel loader is equipped with a cab which is a space for an operator to operate the construction machinery. The cab is usually formed by being enclosed by windows, walls, and the like, and the inside of the cab is designed to have reduced noise.
An example of the cab is disclosed for example in Japanese Patent Laying-Open No. 2007-154444 (PTL 1). In the cab disclosed in Japanese Patent Laying-Open No. 2007-154444, the cab's air tightness is enhanced for reducing noise. In addition, the cab has an air conditioner in the cab, and therefore the inside of the cab is kept comfortable.